Testing device for internal combustion engines



Feb. 11, 1936. 2,030,727

TESTING DEVICE FOR INTERNAL COMBUSTION ENGINES P.G.TURNER Filed June 25, 1933 3 Sheets-Sheet l Feb. 11,1936.

P. G. TURNER TESTING DEVICE FOR INTERNAL COMBUSTION ENGINES Filed June 23, 1953 s Shets-Sheet 2 Feb. 11, 1936.

P. a. TURNER 2,030,727

TESTING DEVICE FOR INTERNAL COMBUSTION ENGINES Filer; Jun 23, 1955" s Sheets-Sheet s I V ii 5 II I :ca E J I 25 Q 2.: 1 25 0 26 i 1 l Tag 4 Patented Feb. ll, 1936 UNITED STATES TESTING DEVICE FOR INTERNAL COMBUSTION ENGINES Price G. Turner, Yorkville, N. Y., assignor of onehalf to John C. McMurray Winthrop, Mass.

Application June 28, 1933, Serial No. 677,281

4 Claims. (Cl. 175-183) My invention relates to a testing device for internal combustion engines and I declare the following to be a full, clear, concise and exact description thereof sufllcient to enable .anyone skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings in which like reference characters refer to like parts throughout the specification.

The object of the invention is to provide a testing device that can be detachably' connected to an internal combustion engine to ascertain in a few seconds the relative working condition of the various mechanical parts of the engine including more particularly the complete ignition system,

such as the breaker points, condenser coil, distributor wiring and spark plugs as well as the rings, pistons and valves of each cylinder. The device will be useful also in determining the location of foreign or abnormal noises in an engine, such as loose wrist pins, bearings, etc. The object will be understood by referring to the drawings,

in which, r i Fig. 1 is a perspective view of the device.

'2 Fig. 2 is a detail view showing a perspective of the switch'mechani'sm and electrical circuits, parts being broken away.

Fig. 3 is a fragmentary view showing a vertical section taken on the line 3, 3 of Fig. 1.

0 c Fig; 4 is a fragmentary view showing a vertical section taken on the line 4, 4 of Fig. 1.

Fig. 5 is a plan view of a modified form of the device.

Fig. 6 is a diagrammatic view of the electric 35 circuits.

Referring more particularly to the drawings, the device is enclosed in a casing made of wood or other suitable material, which has a removable base part 2, whereby to give access to the interior for the insertion and replacement of parts.

'Basepart 2 maybeheldinpositioninanysuitable manner as by screw plugs 3. The top part i of casing I is covered by a metallic plate I made of a good electrical conductor. Plate 5 has apertures 6 for the disposition ofelectric conductor sleeves or bushings I through which slide plunger switchesl, 9,10, II, l2, I, I4 and I. Nuts I casing l8, whereby to hold said top portion i! to the under side of plate 5. Furthermore, top por- 55 tion I1 is made of an insulator. Plunger switches 9, In, H, I2, l3, l4 and I5 are arranged in rows of four each. An auxiliary casing i8 is used for each set of four plunger switches, where eight only are used. Auxiliary-casings l8, I8 are made of an insulator. Plunger switches 8, 9, l0, II, l2, 5 l3, I4 and I! are made of an electric conductor material. The lower end thereof rests in each instance against its respective insulator gate member it. Each of the gate members I9 is pivotally supported at 20, upon a shaft that is 10 mounted in the sides ofauxiliary casing it. Each of the gate members I9 is held normally in horizontal position by a. rubber band 2| or other suitable yielding device such as a spring, whereby to hold the plunger switches in elevated po- 15 sition and thereby also form an insulation between electric contact points of switches, 8. 9,10,

ll, l2, l2, l4 and I! as hereinafter described. A rubber band 2| is used preferably because of its insulator qualities.

Gate I9 is pushed downward against the tendency of the rubber 21 by the actuation of its corresponding switch 8, 9 etc. downward, whereby to allow the lower end of the respective plunger switch to make an electrical contact with the upper end 22 of one of the electrical conductor plugs 23 which are mounted in the base part 24 of auxiliary casing It. When in lower position gate It tends to holdswitch 8, 9 etc. downward in contact with plug 2:. Each of the plugs 21 is connected by an electric wire 25, 26, 21, 28, 29, 20, 3|, 22 as hereinafter more fully explained.

Although eight of the plunger switches with their co-operating gates are employed in the present device any number may be used if found desirable. g

Each of the two auxiliary casings 18, II is dividedinto compartments 33 for housing a gate l8. Furthermore, each of the gates I9 is made 40 of someinsulating material such as Bakelite toprevent any current passing between the lower end of plunger switch 8 and the upper surface of electrical plug 22. 1

The two auxiliary casings l8, it are held in suspended position with reference to their top portions I1, I! andto the electrical cover plate 5 by a bolt 26' that projects downward through plate 5 and engages a cross member 21 which underlies the bottom surface of each of the auxiliary casings II, II. This construction allows for lowering each of the casings i8, it in a convenient manner for purposes of inspecting the interior. I

A collar member 31a is formed integral with each 01' the plunger switches 8, 3, etc., to limit the upward movement thereof.

There is also employed in the casing I another auxiliary casing made of an insulator and which is suspended from cover 5 by screw bolts 4 I. Aux-- iliary casing 48 holds within its' interior a pivotally mounted member 42 which has within its interior a neon tube 43. Neon tube 43 isheld in suspended position by electric conductor springs 44, 45 disposed at opposite ends thereof and engaging the conical ends of neon tube 43. Member 42 is mounted to turn with rotatable pivot member 48.

Pivot member 48 has a bearing in the lower part 41 of auxiliary casing 48 and at its upper end in the cover part 48 ,of auxiliary casing 48 and also cover 5. A, wing or thumb member 58 is attached to the upper end-of rotatable pivot 48, whereby to turn said pivot 46 and also member 42 therewith. Tube 43 has electric conductor cups 5| and 52 mounted upon its opposite ends. An electric coil spring 53 is disposed between the upper surface of cup 52 of member 42 and the undersurface of cover 5, whereby to make an electric connection between plates 5 and cup 52. Solder 54 is used to hold pivot 46 to cup 52, whereby to turn together.

The outer or free end of member 42 provided with metallic cap 5| is adapted to make contact with the several electric contact points 56, 51, 58, 59, 68, 8|, 82, 63 when moved into contact with any one thereof. A rack 64 having notches 65 tends to hold temporarily neon tube 43 on one of the contact points 58 etc.

Plate 5 is grounded by electric wire '86 which is attached at one'end toterminal post 61 mounted to said plate 5 and at the other end to any part of the automobile chassis.

Each'of the wires 25, 26, 21, 28, 28, 38, 3| and 32 has a spring gripping device 68 attached at its free end; whereby to'connect each of said wires with the'respective spark plugs68, whereas each of the electric contact points 56, 51, 58, 59, 68, 6|, 62 and 83 is capacitively connected by an electric wire 18, 1|, 12, 13, 14, 15, 16 and 11 with wires 25, 26, 21, 28, 29, 38, 3|, and 32.

In making this latter connection the insulation is scraped off the ends of wires 18, 1|, 12, 13. 14, 15, 18 and 11 and the scraped part twisted about the insulation on the respective wires 25, 26, 21, 28, 29, 38, 3|, and 32. This is done to provide suillcient resistance in the electric circuit hereinafter described to meet the requirements of the highly sensitive neon tube 43 and yet not cause any interruption of the electric current to the spark plug joints.

. Electric circuits The electric circuit through neon tube 43 is traced as follows: When the plunger switches 8, 8 etc. are open current flows from the coil I81 to the spark plugs 69 etc. across the spark gap to ground and back to the coil I81. If, during such action, the neon tube 43 is in contact with one of the points 56 to 63, say 51 as shown in Fig. 6, the voltage pressure in wire 21 will set up a capacity induced-currentin the neon tube 43 across'the insulated connection between wire 21 and 1|. This capacity-induced current, which is a very small one, will flow from this connection through the neon tube 43 to plate 5, wire 68, to ground.

-The coil current. however, will flow to ground ance spark gap in that plug, will flow, across the top of the plug by connection 68 through one of sive, without interfering with the regular operation of said spark plugs.

, Assuming there is trouble in the spark plugs, distributor, coil, insulation of the wiring etc., the

operator will connect grips 68 at the ends of wires 25-32, inclusive, to said spark plugs and turn neon tube 43 successively to electric contact points 56 to 63, inclusive. Assuming further that the operator has made a test of spark plug 690 by moving neon tube 43 to electrical contact point 56 and found said spark plug 890 to be functioning in a normal manner, he will now turn tube 43,

upon electrical contact point 51 as shown in Fig. 2, thereby eflecting a circuit as follows: spark plug 893, wire 21, through the insulation of wire 21, to wire 1| to electric contact point 51 to neon tube 43, to metallic cover 5, to terminal, post 61,

to wire 86,'to ground.

It will be noted in this circuit, that the insulation on wire 21 which has not been removed in connecting wire 1|, although the insulation has been removed from wire.1|, prevents a complete direct electric circuit through the spark plug 883; but on the other hand this, connection furnishes a current induced by capacity or condenser action of the spark plug 883 current across the insulation on the wire 21 at its junction with wire 1| which acts as a condenser to affect the neon tube 43, whereby the working of the particular spark plug 693 in question can be determined without interrupting its operation.

If now, the light in neon tube 43 is bright, it

. would indicate that .the current passing through the spark plug 833 is of normal strength. If on the other hand, the light is weak or dull. it would indicate that the electric system through spark plug 683 was not functioning normally. This ,1

might be due to several causes such as poor plugs, poor insulation wiring from distributor to plug, poor coils, poor condenser, dirty or cracked distributor cap.

In testing for poor spark plug 633, the operator 5 would disconnect high tension wire |88 that connects the distributor I 8| with a spark plug 883 from said spark plug 693, and connect grip 68 of wire 21 directly to high tension wire |88, thereby eliminating plug 633, the other circuits remain-- ing the same. It now, under these circumstances, neon tube 43 shows a bright or normal light, it indicates that trouble or loss of current was in the spark plug 893. If the light in neon tube 43 still remains dim. however, then the operator would disconnect wire |88 from terminal I82 on distributor |8I and connect the grip 68 of wire 21 with said terminal I82. If-the light is now bright or normal in the neon tube 43, it indicates the loss of current was due to poor insulation on wire |88.

If the light is still dim, the operator would move grip 68 into contact with terminus I88 01 the distributor 8| which terminus is connected by wire I86 with coil I81. If the light is now bright,

it would indicate the trouble was inside the distributor cap due to either dirt collecting inside the distributor cap or a leaky rotor.

If the light is still dim, the operator would change grip 68 from terminus I05 to terminus III of coil I01. If now, the light in neon tube 43 is bright, it would indicate the trouble or loss of current was due to wire I06.

If the light is still dim, however, the trouble has been traced back to its source in coil I01. It will be observed, therefore, that by process of elimination of the several parts of the electric system, the trouble can be traced to its source.

If all the parts in the system above enumerated are working in normal condition, then the operator would make further test by moving neon tube 43 to electric contact .point 58 and in turn, 59, etc.

Additional tests are provided for as follows:

Assuming that some one or more of the cylinders of the engine are defective, the operator in order to ascertain the trouble will use the plunger switches 8 to I in the manner now to be described.

The throttle of the engine will be left wide open, whereby to assure the operation of the engine when running even with only one cylinder. The operator would push down then plunger switches 9 to I 5 inclusive, allowing plunger switch 8 only to stand. By pushing down plunger switches 9 to I5 inclusive, the regular electric circuits through the corresponding spark plugs 89A to 69G, wires 28 to 32, electric contacts 22,

plungers 9 to I5, bushings I, metallic plate 5, wire 55 to ground are closed to short circuit all spark plugs except plug 69.

If the engine runs with only one cylinder corresponding to spark plug 69 operating, it would indicate that this cylinder was not dead. How- 'ever, any weakness in said cylinder would be readily detected by the velocity with which it turned over the crankshaft, not shown, in the engine. If it turned over said crankshaft slowly, it would indicate weakness in some of the parts and it it turned it over rapidly it would indicate a normal condition.

If, on the other hand, it was found that this cylinder was working normally then the operator would push down plunger switch 8' and raise plunger switch 9, allthe other plunger switches I0- to I5, inclusive, remaining down, whereby to determine the normalcy of the cylinder corre: sponding to spark plug 69A. If no defect was found in this cylinder,- the operator would prograss in a similar manner with each of the remaining plungers I0 to I5 inclusive, allowing one to stand and pushing Ewn all the others. By this proceeding, the operator would determine the weak cylinders in the engine.

It will be observed that when a single cylinder is operating to turn over the crankshaft, any abnormal noises as occur because-of loose wristpin, loose bearing or loose piston, would be readily detected and could be remedied. a.

Hereinbefore, the system controlled by neon tube 43 and that controlled by the plunger switches 8 to I5, inclusive, have been described separately. In actual operation, however, the two are used jointly. After attaching the grips 68 to the respective spark plugs 69 to 63G, inclusive, the operator would push down all the plunger switches 9 to I5 inclusive, allowing only plunger switch 8 to stand, thereby short circuiting the electric systems through said several spark plugs 69A to 69G inclusive, excepting 58.

glue is placed upon this one cylinder.

The operator now moves neon tube 43 upon electric contact point 59 corresponding to plungerswitoh 8.

It will be observed that under these conditions, namely, with short circuiting all the spark plugs, 69A to 69G inclusive, allowing only spark plug 69 to remain active that the entire load of the en- Thisgives the most extreme conditions for testing the various parts, both electrical and mechanical,

heretofore mentioned with reference to neon tube 43 and plunger switches 8 to I5 inclusive.

It can readily be seen that the comparison of lights will be of great significance to the operator of this device.

Figure 5 shows a modification intended for use as permanent equipment on airplanes. In this structure a neon tube tube 43 is used in circuit with each of the plunger switches, whereby the pilot can keep a constant check on the working of each individual cylinder of the engine or engines of the airplane and thereby determine at a glance any trouble.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is as follows:

l. Ina testing device for internal combustion engines having spark plugs and electric circuits connected thereto, a portable casing, electric plugs mounted in said casing, plunger switches, whereby to make contact with said electric plugs, members pivotally mounted in said casing, whereby to control the movements of said switches and insulate the switch contacts when said switches are open, wires connected with said electric plugs, fasteners on the ends of said wires, whereby to be connected with said spark plugs, other wires capacitively coupled to said first named wires, electric contact points connected with said second named wires, and a neon tube pivotally mounted in said casing, whereby to be moved into contact with said last named electric contact points to indicate the condition of the electric circuits through said spark plugs.

2. In a testing device for internal combustion engines having spark plugs, a portable casing, auxiliary casings mounted in,said portable casing, wires connected to said auxiliary casings, the ends of said wires having means for attaching them to said spark plugs, switches mounted in said auxiliary casings, whereby to make and break the electric circuits through said wires, means pivotally mounted in said auxiliary casings, whereby to, control the movements of said switches and insulate the switch contacts when said switches are open, a pivotally mounted neon tube in electrical relation to said electric circuits, whereby to indicate the condition thereof to determine defects in the engine and a wire for grounding said first named wires. i

3. In a testing device for internal combustion engines having a coil and spark plugs and electric circuits connected thereto, means for short circuiting said electric circuits, said means comprising other electric circuits, plunger switches mounted in said other circuits, wherebyto short circuit said first named electric circuits, gates pivotallymounted in said auxiliary casings,

whereby to' control the movements of said switches and-insulate the switch contacts when said switches are open, and a neon tube mounted to be moved into connective relation to any one of said second named electric circuits, whereby to indicate the condition of said first named cir- 1 cults.

4. A twter for internal combustion engines comprising a supporting base, a plurality of circuit connections leading from the base and adapted to be connected to the spark plugs of the engine, a ground connection, a; plurality of switcheleinents by which each circuit connection can be connected to the ground connection, a. swinging arm pivoted to said base, and a neon gas tube carried by said am and adapted by the swinging movement thereof to be brought into flashing relation to any one of the circuit connections.

- PRICE G. TURNER. 

